Overmold technique for peel-away introducer design

ABSTRACT

A method for manufacturing a medical introducer includes placing an introducer sheath onto a mandrel, and overmolding an introducer hub onto a proximal end of the introducer sheath. The introducer sheath has one or more score lines formed on an inner surface and the mandrel has a number of surface protrusions so that when the introducer sheath is positioned on the mandrel, each of the surface protrusions contacts one of the score lines formed on the introducer sheath. The surface protrusions on the mandrel prevent plastic material from the introducer hub from contacting the score lines thereby maintaining the score lines during the overmolding.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 15/834,783, filed Dec. 7, 2017, which claims the benefit of thefiling date of U.S. Provisional Patent Application No. 62/431,671, filedon Dec. 8, 2016, the entire disclosures of which are hereby incorporatedherein by reference.

BACKGROUND OF THE INVENTION

Peel-away introducers are disposable medical devices used in a cardiaccatheterization or other medical setting to deliver medical devices intothe vasculature. Standard peel-away introducers include a proximalplastic hub coupled to a sheath. Medical devices can be inserted throughthe plastic hub and into the sheath, through which the device can beplaced in a patient's body. Intravascular medical devices, such asintracardiac blood pumps, catheters, guidewires, or leads, can beintroduced into a patient's vasculature through a peel-away introducer.Once the medical device has been positioned, the peel-away introducercan be removed. In one approach, the operator breaks the introducer bycracking the plastic introducer hub and peeling down the shaft of thesheath body. In order to break the peel-away introducer, the operatorgrasps the molded hub and breaks it at the proximal end of the sheathalong axial notches or scorings. The sheath tears along perforations orscorings down one or both sides of the sheath and can be peeled axially.The peel-away introducer allows the introducer to be removed after amedical device is inserted into a patient through the introducer withoutdisturbing or removing the medical device.

In a common manufacturing technique, peel-away introducers are formedfrom an extruded plastic tube with axial notches in a hub body. A hubbody including notches and/or wings to facilitate breaking is overmoldedonto an extruded plastic sheath or tube. The plastic tube is firstassembled over a corepin or mandrel which defines and maintains theinner cavity of the hub and inner diameter and geometry of the sheath.The mandrel and extruded sheath are then placed into a mold cavityallowing for molten plastic to be injected and cooled, creating theplastic hub that the user breaks to initiate peeling.

In the overmolding technique, after the mandrel and extruded sheath areplaced into a mold, molten plastic in injected into the mold. Theplastic cools around the sheath in the shape of the mold, forming thehub body. The injected plastic is maintained at a high temperature whenit is introduced to the mold, and the heat from the injected plasticsurrounding the sheath may be sufficient to heat a top layer of thesheath plastic such that the plastic of the sheath may start to flow ina process called reflowing. The portion of the sheath disposed insidethe hub of the assembly may lose its internal scoring or notching duringthe molding process if the heat of the injected plastic reflows into oneor more of the scores/notches. As a result, the forces required to breakthe hub may be excessive or inconsistent because the sheath does notinclude a weakened section of one of the scores/notches. Furthermore,when the plastic of the sheath is reflowed and the scoring is removed inthe section of the sheath within the hub, there is an increased riskthat during the breaking of the hub the tear will not propagate to thescoring in the sheath body outside the section in the overmolded hubleading to a defective peel-away introducer sheath.

SUMMARY OF THE INVENTION

Described herein are methods and systems for producing a peel-awayintroducer including an overmolded hub while maintaining the scoring ofthe sheath. During overmolding, a mandrel designed with outer surfaceprotrusions on which the sheath is assembled, maintains the innerscorings of the sheath through the injection molding process despite theapplication of extreme heat. With the internal scorings of the sheathmaintained, when the hub is broken by an operator, the proximal sectionof the sheath tube in the overmolded hub breaks more easily and withless required force. Sheaths manufactured by the methods disclosedherein can also peel more easily.

In one aspect, a method for manufacturing a medical introducer includesplacing an introducer sheath onto a mandrel, and overmolding anintroducer hub onto a proximal end of the introducer sheath. Theintroducer sheath has one or more score lines formed on an innersurface. The mandrel has a number of surface protrusions so that whenthe introducer sheath is positioned on the mandrel, each of the surfaceprotrusions contacts one of the score lines formed on the introducersheath and prevents plastic material from the introducer hub fromcontacting the score lines.

In some implementations, the number of surface protrusions on themandrel is equal to the number of score lines formed on the sheath. Insome implementations, the introducer hub includes a number of notches.In some implementations, the number of notches in the introducer hub isequal to the number of score lines formed on the sheath and also equalto the number of surface protrusions on the mandrel. In someimplementations, at least one of the number of notches is aligned with ascore line formed on the sheath. In some implementations, at least twonotches are aligned with a score line formed on the sheath. In someimplementations, the introducer hub and introducer sheath are configuredto be broken into at least two pieces along the notches and score lines.

In some implementations, the number of surface protrusions on themandrel is not equal to the number of score lines formed on the sheath.In some implementations, at least one of the number of score linesformed on the inner surface of the introducer sheath is removed duringthe overmolding. In some implementations, the number of surfaceprotrusions on the mandrel is equal to a desired number of score linesin the sheath.

Variations and modifications will occur to those of skill in the artafter reviewing this disclosure. The disclosed features may beimplemented, in any combination and subcombination (including multipledependent combinations and subcombinations), with one or more otherfeatures described herein. The various features described or illustratedabove, including any components thereof may be combined or integrated inother systems. Moreover, certain features may be omitted or notimplemented.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects and advantages will be apparent uponconsideration of the following detailed description, taken inconjunction with the accompanying drawings, in which like referencecharacters refer to like parts throughout, and in which:

FIG. 1A shows a top view of an introducer hub molded over a sheathduring the manufacture process according to an embodiment;

FIG. 1B shows a perspective view of a mandrel having both continuoussurface protrusions and surface protrusions configured as a series ofprotrusions;

FIG. 2 shows a perspective view of a mandrel being inserted into asheath during the manufacture process according to an embodiment;

FIG. 3 shows a perspective view of a mandrel fully inserted into asheath during the manufacture process according to an embodiment;

FIG. 4 shows a perspective view of a mandrel having a surface protrusionaccording to an embodiment;

FIG. 5 shows a perspective view of a peel-away introducer hub assemblyaccording to an embodiment;

FIG. 6 shows an alternative view of a peel-away introducer hub accordingto an embodiment; and

FIG. 7 shows a method for manufacturing a peel-away introducer hubaccording to an embodiment.

DETAILED DESCRIPTION OF THE DRAWINGS

Following below are more detailed descriptions of various conceptsrelated to inventive methods of manufacturing a peel-away medicalintroducer. It should be appreciated that various concepts introducedabove and discussed in greater detail below may be implemented in anynumber of ways, as the disclosed concepts are not limited to anyparticular manner of implementation. For example, though peel-awayintroducer sheaths are depicted herein having two axial notches whichdivide the introducer hub and underlying sheath into two sections, theintroducer hub and sheath may be manufactured to have any number ofaxial notches or perforations so as to allow parting into any number ofportions along an axial direction. Furthermore, although surfaceprotrusions of a mandrel are described with reference to maintainingscore lines on a sheath for use in a peel-away introducer, the surfaceprotrusions on the mandrel may be used to protect other features of theinternal geometry of a sheath during any overmolding or heat-treatingprocess. Examples of implementations and applications are providedprimarily for illustrative purposes.

The methods and systems described herein enable production of apeel-away introducer including an overmolded hub while maintaining thescoring of the sheath. The mandrel for holding the hub and the sheathcan have one or more outer elongate protrusions formed along an outersurface thereof. A protrusion can contact each of the correspondinginner scorings of the sheath so that when heat is applied the scorelines are maintained through the injection molding process rather thanfilled with material from the hub or the sheath (e.g., plastic that hasmelted during heat application). With the internal scorings of thesheath maintained, when the hub is broken by an operator, the proximalsection of the sheath tube in the overmolded hub breaks more easily andwith less required force than if this material had flowed into the scorelines and hardened. Additionally, with the score lines in the introducersheath maintained, the hub can be broken and the sheath peeledlongitudinally to facilitate removal of the introducer hub assembly. Theovermolding method described herein promotes appropriate breaking of theintroducer hub and peeling of the sheath as designed.

FIG. 1A shows a top view of an introducer hub and mandrel assembly 100including a hub body 112 molded over an introducer sheath 104 during themanufacture process. The introducer hub assembly 103 includes anintroducer sheath 104, a first score line 110 a, a second score line 110b, a hub body 112, a first notch 114 a, a second notch 114 b, a firstwing 116 a, and a second wing 116 b. The first score line 110 a and thesecond score line 110 b are on opposite sides of the introducer sheath104. The introducer sheath 104 is positioned over a mandrel 101 (alsocalled a corepin) having a first surface protrusion 102 a and a secondsurface protrusion 102 b on opposite sides of the mandrel 101. The firstsurface protrusion 102 a and the second surface protrusion 102 b areconfigured to coincide with the first score line 110 a and the secondscore line 110 b in the introducer sheath 104. After the introducersheath 104 is positioned over the mandrel 101 with the first surfaceprotrusion 102 a and the second surface protrusion 102 b aligned withthe first score line 110 a and the second score line 110 b in theintroducer sheath 104, the introducer hub body 112 can be overmoldedover the proximal end of the introducer sheath 104. The first notch 114a and the second notch 114 b are aligned with the first score line 110 aand the second score line 110 b in the introducer sheath 104 tofacilitate breaking of the introducer hub assembly 103.

The mandrel 101 with the first surface protrusion 102 a and the secondsurface protrusion 102 b is shaped to maintain the inner geometry of theintroducer sheath 104. The introducer sheath 104 fits tightly over themandrel 101 in preparation for overmolding of the introducer hubassembly 103. There may be some distance 106 between an outer surface108 of the mandrel 101 and an inner surface 105 of the introducer sheath104, but in most cases the distance 106 is minimized such that the outersurface 108 of the mandrel 101 is in contact with the inner surface 105of the introducer sheath 104 in areas which are to be protected duringovermolding, such as at the first score line 110 a and the second scoreline 110 b. In some implementations, the distance 106 between the outersurface 108 of the mandrel 101 and the inner surface 105 of theintroducer sheath 104 in areas which are not protected duringovermolding is e.g., 0 mm, 0.1 mm, 0.2 mm, 0.3 mm, or 0.4 mm or it canbe structured at any other suitable distance. The surface protrusions102 a and 102 b may be set at a desired height from the body of themandrel 101. In some implementations, the surface protrusions 102 a and102 b extend from the surface of the mandrel 101 by about 0.05 mm, 0.1mm, 0.2 mm, 0.3 mm, or any suitable height. In certain embodiments, thedistance between the outer surface 108 of the mandrel 101 and an innersurface 105 of the introducer sheath 104 is between about 0 mm and 0.4mm, while the protrusions extend from the outer surface 108 of themandrel 101 and have a height of about 0.05 mm to 0.3 mm. In someimplementations, the surface protrusions have a shape which is square,rectangular, cylindrical, or any other suitable shape. In someimplementations, the protrusions extend longitudinally along themandrel. In some implementations, the protrusions extend in a helixalong the mandrel.

With the introducer sheath 104 fit over the mandrel 101, the introducerhub assembly 103 can be formed onto the sheath 104 such as by beinginjection molded over the introducer sheath 104. The injection moldingprocess exposes the proximal end of the introducer sheath 104 to hightemperatures and/or pressures which can cause reflow of the plastic fromwhich the introducer sheath 104 is formed. Reflowing plastic may coveror completely fill the first score line 110 a and the second score line110 b in the introducer sheath 104 if the first score line 110 a and thesecond score line 110 b are not protected by a corresponding protrusion.The first surface protrusion 102 a and the second surface protrusion 102b extend into the first score line 110 a and the second score line 110 bsuch that even if the introducer sheath 104 is heated and reflow occurs,the first score line 110 a and the second score line 110 b aremaintained.

If the first score line 110 a and the second score line 110 b arealtered or removed by reflow of the plastic during construction, theintroducer sheath 104 may not separate properly during breaking of theintroducer hub assembly 103 after use. The hub body 112 may break asdesigned at first notch 114 a and second notch 114 b when an outward ordownward force is applied to the first wing 116 a and second wing 116 b.However, if the first score line 110 a and the second score line 110 bhave been damaged, the separation may not propagate to the introducersheath 104, or from a proximal portion of the introducer sheath 104 to amore distal portion not in contact with the introducer hub assembly 103.As a result, it may be difficult or uncomfortable for an operator toapply the additional or excessive force required in order to initiatethe breaking of the introducer hub assembly 103.

Though the introducer sheath 104 is depicted here having two scorelines, the first score line 110 a and the second score line 110 b, theintroducer sheath 104 may be configured with any number of score lines.In some implementations, the introducer sheath is configured with onescore line, two score lines, three score lines, four score lines, sixscore lines, ten score lines, or any other suitable number of scorelines. The score lines may be formed as perforations, scorings,indentations or by any other suitable means.

The mandrel 101 is depicted here having two surface protrusions, thefirst surface protrusion 102 a and the second surface protrusion 102 b,but may have any suitable number of surface protrusions. In someimplementations, the mandrel 101 has one surface protrusion, two surfaceprotrusions, three surface protrusions, four surface protrusions, sixsurface protrusions, or any other suitable number of surfaceprotrusions. The mandrel 101 may have a number of surface protrusionsequal to the number of score lines on the introducer sheath 104.Alternatively, the mandrel 101 may have a number of surface protrusionswhich is less than the number of score lines on the introducer sheath104. If the number of surface protrusions is less than the number ofscore lines on the introducer sheath 104, any additional score lines onthe introducer sheath 104 may be removed by reflow of material duringthe manufacture of the introducer hub assembly 103 overlay. For example,if an introducer sheath 104 has three score lines, but only two aredesired for an introducer hub assembly a mandrel with only two surfaceprotrusions may be used to protect two of the three score lines on theintroducer sheath during overmolding. Alternatively, the mandrel 101 mayhave a number of surface protrusions that is greater than the number ofscore lines on the introducer sheath 104 such that only some of thetotal surface protrusions contact the score lines. This can allow, forexample, the mandrel 101 to be configured to assemble sheaths havingvarying number of score lines.

The surface protrusions on the mandrel 101 may be matched to the type ofscore lines on the introducer sheath 104, as shown in FIG. 1B. FIG. 1Bincludes a mandrel 101 extending from a base 120 with a first surfaceprotrusion 122 a and a second surface protrusion 122 b. The firstsurface protrusion 122 a is configured as a continuous protrusion fromthe outer surface of the mandrel 101 which would contact a score line ofan introducer sheath along an entire length without interruption. Thesecond surface protrusion 122 b is configured as a series of surfaceprotrusions arranged in a line along the mandrel 101. The second surfaceprotrusion 122 b contacts the introducer sheath only at each of theindividual protrusions, and not at the space between the protrusions.For example, a series of surface protrusions such as second surfaceprotrusion 122 b may be used to protect a score line configured as aperforation.

FIG. 2 shows a perspective view of a mandrel 201 partially inserted intoan introducer sheath 204 in preparation for overmolding of an introducerhub. The mandrel 201 includes a base 220, a first surface protrusion 202a and a second surface protrusion 202 b. The first surface protrusion202 a and a second surface protrusion 202 b are parallel to alongitudinal axis 207 of the mandrel 201. The introducer sheath 204includes a proximal end 209, a first score line 210 a and a second scoreline 210 b aligned parallel to the longitudinal axis 207 of the mandrel201 which coincides with a longitudinal axis 207 of the introducersheath 204 which the introducer sheath 204 is placed on the mandrel 201.The first surface protrusion 202 a and a second surface protrusion 202 bare aligned with the first score line 210 a and the second score line210 b of the introducer sheath 204 in order to protect the score linesand internal geometry of the introducer sheath 204 during overmolding ofan introducer hub at the proximal end 209 of the introducer sheath 204.Introducer sheath 204 is inserted over the mandrel 201 in the directionof arrow 211 prior to the overmolding of the introducer hub.

FIG. 3 shows a perspective view of a mandrel 301 fully inserted into anintroducer sheath 304 in a final configuration prior to overmolding ofan introducer hub onto the introducer sheath 304. The mandrel 301includes a base 320 and one or more surface protrusions 302. Theintroducer sheath 301 includes a first score line 310 aligned parallelto a longitudinal axis 307 of the introducer sheath 304. The surfaceprotrusion 302 is aligned with the first score line 310 to protect thefirst score line 310 from reflow during further processing. Theintroducer sheath 304 is designed to tear along the first score line 310when the introducer hub assembly is broken. However, the first scoreline 310 may become damaged or be removed by the heat from theovermolding of the introducer hub body if the first score line 310 andany other score lines are not protected and maintained. The surfaceprotrusion 302 of the mandrel 301 protects the internal geometry of theintroducer sheath 304 including the first score line 310 during theovermolding of the introducer hub body so that the first score line 310remains. The mandrel 301 is sized to fit inside the introducer sheath304 and the surface protrusion 302 on the mandrel is likewise sized toalign with and correspond to the first score line 310 on the introducersheath 304.

FIG. 4 shows a perspective view of a mandrel 401 having surfaceprotrusions 402 a and 402 b. The mandrel 401 includes a base 420, afirst surface protrusion 402 a, and a second surface protrusion 402 b.The first surface protrusion 402 a and the second surface protrusion 402b extend along the cylindrical mandrel 401 parallel to the longitudinalaxis. The first surface protrusion 402 a and the second surfaceprotrusion 402 b are sized and positioned to correspond to the internalgeometry and score lines of the introducer sheath so that the internalgeometry and space of the introducer sheath is maintained during themanufacture of the introducer hub on the introducer sheath.

Although two surface protrusions 402, the first surface protrusion 402 aand the second surface protrusion 402 b, are shown in FIG. 4 , themandrel 401 can have any suitable number or orientation of surfaceprotrusions to protect and maintain score lines on an introducer sheathplaced over the mandrel 401. The mandrel 401 may have one, two, three,four, six, eight, or any suitable number of surface protrusions. In someimplementations, the mandrel 401 includes the same number of surfaceprotrusions as the number of score lines on the introducer sheath. Insome implementations, the mandrel 401 includes a smaller number ofsurface protrusions than the number of score lines on the introducersheath. In such cases, the additional score lines on the introducersheath will be removed by reflow of the plastic of the sheath during theovermolding process. Removal of unnecessary score lines duringovermolding by not protecting the score lines with the mandrel may allowmultiple styles of introducer hub assemblies to be prepared using asingle type of introducer sheath. The surface protrusions may be alignedalong the longitudinal axis 407 as shown here, or they may be orientedat an angle to the longitudinal axis or in a spiral orientation aroundthe outer surface of the mandrel.

The first surface protrusion 402 a and the second surface protrusion 402b shown in FIG. 4 are depicted as continuous raised sections of themandrel 401. In some implementations, the surface protrusions on themandrel 401 are configured as a series of raised dots in order toprotect the specific geometry of the interior of the introducer sheath.In some implementations, the surface protrusions may be a continuousraised section configured as a ridge with an angled top, a squared topor a rounded top. The shape of the surface protrusions may be matched toa shape of the score lines in the introducer sheath.

FIG. 5 shows a perspective view of a peel-away introducer hub assembly503. The peel-away introducer hub assembly 503 includes a hub body 512,a first wing 516 a, a second wing 516 b, a first notch 514 a, a secondnotch 514 b, an introducer sheath 504, a first score line 510 a, asecond score line 510 b, and a throughgoing cavity 524. The first notch514 a is aligned with the first score line 510 a, and the second notch514 b is aligned with the second score line 510 b. The first wing 516 aand the second wing 516 b extend on opposite sides of the hub body 512,such that the first notch 514 a and the second notch 514 b arepositioned between the first wing 516 a and the second wing 516 b.

A medical device or catheter may be inserted into a patient through thethroughgoing cavity 524 in the introducer hub assembly 503. After thedevice or catheter has been inserted, an operator can break theintroducer hub assembly 503 by applying a force to the first wing 516 aand the second wing 516 b, breaking the introducer hub assembly 503 intotwo or more pieces. The introducer hub assembly 503 is designed to breakat the first notch 514 a and the second notch 514 b upon the applicationof this force on the first wing 516 a and the second wing 516 b. Thealignment of the first notch 514 a and the second notch 514 b with thefirst score line 510 a and the second score line 510 b, respectively,allows the break force applied by the operator to break the hub body 512to propagate from the first notch 514 a to the first score line 510 aand from the second notch 514 b to the second score line 510 b to allowthe introducer hub assembly 503 to be broken into two pieces and theintroducer sheath 504 to be peeled away. Good alignment of the notcheswith the score lines that have been protected from damage during theovermolding of the hub body 512 allows the introducer hub assembly to beeasily broken and peeled with a nominal breaking force applied.

FIG. 6 shows an alternative view of the peel-away introducer hub 503 ofFIG. 5 , illustrating the alignment of the second notch 614 b with thesecond score line 610 b opposite the first notch 614 a and first scoreline 610 a. The first wing 616 a, second wing 616 b, and cavity 624 ofFIG. 6 are the same features described above with respect to first wing516 a, second wing 516 b, and cavity 524 of FIG. 5 , respectively. Thealignment of the second notch 614 b with the second score line 610 b(and first notch 614 a and first score line 610 a) allows the transferof the breaking force from the hub body 612 to the introducer sheath604. If the score line 610 of the introducer sheath 604 has not beendamaged or removed by the flow of plastic material from the introducersheath 604 during the overmolding of the introducer hub body 612, theforce may be propagated from the hub body 612 to the introducer sheath604 without incident.

If the score line 610 of the introducer sheath 604 has been damaged orremoved by the reflow of plastic material from the introducer sheath 604during overmolding, the introducer sheath 604 may not easily split apartat the hub body 612 or below the hub body 612. This may requireadditional or excessive force to be applied to the hub body 612 or tothe introducer sheath 604 in order to break the hub body 612 andintroducer sheath. Alternatively, the malfunction of the introducer hubassembly 603 due to damaged score lines in the introducer sheath 604 mayresult in a defective introducer hub assembly which cannot be peeledaway as designed. Alternative or suboptimal methods for removal may thenbe used which may require additional tools.

FIG. 7 shows a method 700 for manufacturing a peel-away introducer hub,such as the introducer hub assembly 103 of FIG. 1A, hub assembly 503 ofFIG. 5 , or any other suitable hub assembly. At step 702 the methodincludes placing an introducer sheath on a mandrel including a number ofsurface protrusions. The surface protrusions are designed to contactscore lines in an interior surface of the introducer sheath in order toprotect the geometry of the interior of the introducer sheath includingthe score lines. The mandrel may include the same number of surfaceprotrusions as the number of score lines on the introducer sheath, or insome implementations, the mandrel includes a smaller number of surfaceprotrusions if a number of score lines are designed to be removed duringthe next step. The mandrel and extruded sheath are then placed into amold cavity allowing for molten plastic to be injected and cooled.

At step 704, the surface protrusions of the mandrel are aligned with thescore lines of the introducer sheath. The introducer sheath fits tightlyover the mandrel and the score lines on the interior of the introducersheath are in contact with the surface protrusions of the mandrel. Insome implementations, the surface protrusions of the mandrel may bealigned with the score lines of the introducer sheath before the mandrelis inserted into the introducer sheath, or simultaneous to insertion.The shape, size, and height of the surface protrusions may be matched tothe score lines in the introducer sheath. In some implementations, thesurface protrusions may be a continuous raised section configured as aridge with an angled top, a squared top or a rounded top. The surfaceprotrusions on the mandrel may be a variety of heights from the body ofthe mandrel to match the score lines in the introducer sheath. In someimplementations, the surface protrusions extend from the surface of themandrel by 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, or any suitable height. Insome implementations, there is some distance between an outer surface ofthe mandrel and an inner surface of the introducer sheath, but in mostcases the distance is minimized such that the outer surface of themandrel is in contact with the inner surface of the introducer sheath atleast in regions which are to be protected from reflow during furthermanufacture. In some implementations, the distance between the outersurface of the mandrel and the inner surface of the introducer sheath inareas which are not to be protected is 0 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4mm or any other suitable distance. In some implementations, the surfaceprotrusions 102 a and 102 b extend from the surface of the mandrel 101by about 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, or any suitable height. Incertain implementations, the distance between the outer surface of themandrel and an inner surface of the introducer sheath is between about 0mm and 0.4 mm, while the protrusions extend from the outer surface ofthe mandrel and have a height of about 0.05 mm to 0.3 mm.

At step 706, the method includes overmolding an introducer hub onto aproximal end of the introducer sheath. The overmolding process usesheating, which may cause the plastic material of the introducer sheathto melt and reflow. The areas of the score lines which are protected bytheir contact with the surface protrusions of the mandrel are notcovered by reflowing plastic and are maintained throughout theovermolding process. Areas which are not protected by the surfaceprotrusions on the mandrel may reflow and fill in any additional scorelines.

The overmolding of the introducer hub may also include overmolding oneor more wings onto the introducer hub to aid in the breaking of the hubafter use. After the introducer hub is overmolded onto the proximal endof the sheath the introducer hub and introducer sheath are removed fromthe mandrel. The introducer sheath includes a number of score lineswhich have been maintained by the mandrel during the overmolding of theintroducer hub and introducer hub body. The score lines correspond tonotches in the overmolded introducer hub. The introducer hub may beseparated into two or more pieces at the notches and score lines afteruse with the application of a nominal force on the wings. Once theintroducer hub has been separated at the notches and score lines, theintroducer sheath may be peeled away along the score lines to remove theintroducer hub assembly.

The foregoing is merely illustrative of the principles of thedisclosure, and the methods and systems can be practiced other than thedescribed implementations, which are represented for purposes ofillustration and not of limitation. It is to be understood that themethods and systems disclosed herein, while shown for use in manufactureof a peel-away introducer hub and sheath, may be applied to othersystems in which internal geometries of a sheath must be maintainedduring heat treatment.

Variations and modifications will occur to those of skill in the artafter reviewing this disclosure. For example, the geometries andorientations of the surface protrusions of the mandrel can bebeneficially chosen to match an internal geometry of the introducersheath, or to complement an internal geometry or desired internalgeometry. The disclosed features may be implemented, in any combinationand subcombination (including multiple dependent combinations andsubcombinations), with one or more other features described herein. Thevarious features described or illustrated above, including anycomponents thereof, may be combined or integrated in other systems.Moreover, certain features may be omitted or not implemented.

Examples of changes, substitution, and alterations are ascertainable byone skilled in the art and could be made without departing from thescope of the information disclosed herein.

The invention claimed is:
 1. A method of manufacturing a medicalintroducer, comprising: placing an introducer sheath on a mandrel, theintroducer sheath having one or more score lines formed on an innersurface thereof; and overmolding a plastic material onto a proximal endof the introducer sheath to form an introducer hub using a mold that:(i) surrounds the proximal end of the introducer sheath, and (ii)includes at least one projection aligned with a given score line of theone or more score lines, wherein the mandrel includes one or moresurface protrusions, and wherein the introducer sheath is positioned onthe mandrel such that a given surface protrusion of the one or moresurface protrusions is aligned with the given score line and causes theplastic material deposited over the inner surface of the introducersheath during the overmolding to be thinner along at least a portion ofthe given score line than at an area adjacent to the given score line.2. The method of claim 1, wherein a number of the one or more surfaceprotrusions on the mandrel is equal to a number of the one or more scorelines formed on the introducer sheath.
 3. The method of claim 2, whereinthe introducer hub includes a number of notches.
 4. The method of claim3, wherein the introducer hub includes a number of notches equal to thenumber of the one or more score lines formed on the introducer sheathand to the number of the one or more surface protrusions on the mandrel.5. The method of claim 4, wherein at least one of the number of notchesis aligned with a score line of the one or more score lines formed onthe introducer sheath.
 6. The method of claim 5, wherein the introducerhub includes at least a first notch and a second notch, the first notchbeing aligned with a first score line of the one or more score linesformed on the introducer sheath, and the second notch being aligned witha second score line of the one or more score lines formed on theintroducer sheath.
 7. The method of claim 6, wherein the introducer huband introducer sheath are configured to be broken into at least twopieces along the first and second notches and the first and second scorelines.
 8. The method of claim 1, wherein a number of the one or moresurface protrusions on the mandrel is not equal to a number of the oneor more score lines formed on the introducer sheath.
 9. The method ofclaim 8, wherein at least one score line of the one or more score linesformed on the inner surface of the introducer sheath is removed duringthe overmolding.
 10. The method of claim 9, wherein the number of theone or more surface protrusions on the mandrel is less than the numberof the one or more score lines formed on the introducer sheath.
 11. Anintroducer hub manufacturing assembly, the assembly comprising: anintroducer sheath formed as a cylindrical tube having a first end and asecond end, the introducer sheath including on an inner surface thereofat least one score line extending from the first end to the second end;a mold surrounding a first end of the introducer sheath and configuredto enable overmolding of a plastic material onto the first end of theintroducer sheath to form a hub, the mold including at least oneprojection aligned with a given score line of the at least one scoreline; and a mandrel inserted into the introducer sheath, wherein themandrel includes at least one surface protrusion on an exterior surfacethat extends along a length of the mandrel and that is aligned with thegiven score line, wherein a given surface protrusion of the at least onesurface protrusion is configured to cause the plastic material depositedover the inner surface of the introducer sheath during overmolding toform the hub to be thinner along at least a portion of the given scoreline than at an area adjacent to the given score line.
 12. The assemblyof claim 11, wherein the given surface protrusion extends longitudinallydown the mandrel.
 13. The assembly of claim 11, wherein the givensurface protrusion extends helically around the mandrel.
 14. Theassembly of claim 11, wherein the given surface protrusion is configuredas a continuous protrusion.
 15. The assembly of claim 11, wherein thegiven surface protrusion is configured as a series of protrusionsextending down a length of the mandrel.
 16. The assembly of claim 11,wherein the hub is formed from a heated plastic.
 17. The assembly ofclaim 16, wherein the introducer sheath is formed from a plastic whichreflows when subject to heat above a melting temperature of the plastic.18. The assembly of claim 11, wherein the hub includes a first notch anda second notch arranged at opposite sides of the hub.
 19. The assemblyof claim 18, wherein the hub is configured to break at the first notchand the second notch.
 20. The assembly of claim 11, wherein theintroducer sheath is configured to tear along at least the given scoreline when the hub is broken.
 21. The assembly of claim 11, wherein anumber of the at least one surface protrusion is greater than a numberof the at least one score line.
 22. The assembly of claim 11, wherein anumber of the at least one surface protrusion is less than a number ofthe at least one score line.
 23. The assembly of claim 11, wherein anumber of the at least one surface protrusion is equal to a number ofthe at least one score line.